Abstract
The cultivation of Hansenula polymorpha was carried out on ethanol as well as glucose substrates in a bench scale tower bioreactor in batch and “extended culture” (“feed batch”) operations. Following values were measured: The concentrations of cell mass and substrate in the medium as well as the oxygen and CO 2 concentrations in exhaust gas, the local bubble size distribution (Sauter bubble diameter), the local gas hold up and the longitudinal concentration profiles of dissolved oxygen in the medium. The cell productivity, the oxygen transfer rate, substrate and O 2 utilization and CO 2 production rates were calculated and the specific interfacial area, a, and volumetric mass transfer coefficients, k L a, were evaluated as function of the longitudinal distance from the aerator in non limited, substrate limited as well as oxygen transfer limited growth ranges. These systems were simulated by means of a hybride computer and good agreements between calculated and measured data were achieved. The ethanol concentration strongly influences a and k L a. Glucose causes a growth repression already at low substrate concentrations.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
